EFFECT OF INCLINED IMPERVIOUS BOUNDARIES ON UPLIFT PRESSURE ON FOUNDATIONS OF HYDRAULIC STRUCTURES BY ELECTRICAL ANALOGY

Abstract

The scientific treatment of groundwater flow is a relatively recent development. Previously it was not con-sidered possible to analyse a seepage problem analytically. The complications of the heterogeneity of the soil stratum. which represented big hurdles in getting mathematical treat-ment have now been overcome ,,,rith the various advancements in the mathematics of the theory of functions and complex v=zri ahls Rlong --rith various new transformations like Schwarz Christoffel Transformation. 11he tU:o crs~s of situation of lower impervious boundary namely at a finite depth and at an infinite depth from ground level have been theoretically an9lysdd and experimentally verified for the design of hyd-raulic structures. In the first case the lower impervious boundary is taken to be horizontal, parallel to the ground surface and lying at a certain depth from ground level while in the later case it lies at an infinite distance below the ground surface. The present study confines its attention to the in between case of the above two cases where the lower impervious boundary is inclined at an angle with the horizonta., Then with the help of electrical analogy method the equipotential lines are drawn and a flownet is conse-quently obtained. The curves are drawn showing relationship between various dimensionless parameters. These curves refer to very general cases. From these curves the uplift pressure can be easily calculated, for any type of similar problem available in field in practice. So the work thus investigated is directly useful for t'le design of various hydraulic structures placed directly on permeable founda-tions.